A Mighty Fortress (Safehold Book 4)

The Charisian Empire has managed to survive against seemingly impossible odds and has destroyed the armada of the Church of God Awaiting. The Church has spent centuries suppressing all technological development and now finds that its only hope of crushing the Charisian Empire is to permit the use of the technology it went to war to suppress. The Church leaders must also devise a plan to eliminate the new technology once the war is concluded.